The molecular dynamics of focal adhesion kinase in the mechanotaxis of endothelial cell migration

The migration of vascular endothelial cells (ECs) is critical in vascular remodeling. We showed that fluid shear stress enhanced EC migration in flow direction (defined as mechanotaxis). By expressing focal adhesion kinase (FAK) tagged with green fluorescence protein in ECs, we showed that shear stress induced lamellipodial protrusion in the flow direction, with the recruitment of FAK at FAs in lamellipodia. The newly formed FAs subsequently disassembled after the rear of the cell moved over them. The cells migrating under flow had decreased number of FAs. In contrast to shear stress, serum induced lamellipodia and FAK recruitment at FAs without directional preference. The dynamics of FAs was tracked and quantified. Our results demonstrate the dynamics of FAK at FAs during the directional migration of ECs in response to mechanical force, and suggest that mechanotaxis is an important mechanism controlling EC migration.